The Oakland A’s have hired the cutting-edge Danish architectural firm, Bjarke Ingels Group (BIG), to lead the design process for a new ballpark and surrounding development. The firm, which describes its design approach as “pragmatic utopian,” will oversee planning for two possible sites — the waterfront Howard Terminal and the 111-acre Coliseum property in east Oakland. “We wanted a team that could look at the ballpark with a fresh perspective … and this is really a game changer,” said A’s President Dave Kaval.